Method of treating lime-nitrogen.



snares raannr enrich.

ADOLF PAULINUS ZAMORE, OF MANSBO, AND OSCAR FREDRIK CARLSON, OF LJUNGAVERK, SWEDEN, ASSIGNORS TO SAID OARLSON METHOD OF TREATINGLIME-NITROGEN.

Specification of Letters Iatent. Application filed August 6, .1912.

Patented Got. 2a, 1912. Serial No. 713,648.

and resident of Ljunga Verk, Johannisberg,

in the Kingdom of Sweden, have invented certainnew and usefulImprovements in the Method of Treating Lime-Nitrogen, of. which thefollowing is a specification;

The lime nitrogen (calcium cyanamid) which is obtained by heatingcalcium carbid in a nitrogen atmosphere, is after having been ground avery caustic and dusting powder which is difficult to deal with as .wellduring transportation as when it is employed as a fertilizer. Severalmethods have been proposed to remove this causticity and dustiness, forinstance by means of water, oil, water and oil, carbonic acid and water,etc. Dne has also proposed to treat the lime nitrogen with moist nitrousgases, and also to treat the same with nitric acid, containing per cent."of HNO,. All these methods, however, are effected with a great deal ofinconvenience. The treatment with nitrous gases requires a complicatedsystem of apparatus and is difiicult to carry out; furthermore, nitriteis also formed hereby. .Vhen treatin the lime nitrogen with nitric acidcontaining 50 per cent. or more of HNO, great quantities of nitrousgases areformed.

The present invention now refers to a method of treating lime nitrogenwith a mixture of nitric acid and water in such proportions that themixture will correspond to a diluted nitric acid containing 325 percentof HNO,. A suitable quantity of this diluted acid to be added to thelime nitrogen is 15-50 per cent. of the weight of the lime nitrogen. Byusing such a diluted acid the increasing of the-temperat-ure-is verylittle, and by regulating the mass during the reaction between acid andlime nitrogen by cooling one can obtain the result that very little orno ammonia is generated, and that a very inconsiderable quantity, ofdicyan-diamid is formed. The product will also be free from nitrite. Themethod can be performed by means of suitthe temperature of ableapparatus, such as 'niixing screws, mixers with rotating armsor by acombination I of such apparatus. After the mass has been 4 treated1nsaid apparatus with the above I mentioned acid it may be left standingfor some time and thereafter be passed through another apparatusforcrushing lumps which may have been formed.

The lime nitrogen treated in this manner can be obtained as 'anon-dusting powder, which does not dust, even if it has been stored fora considerable time; this is not the case with lime nitrogen having beentreated according to known methods. Fur thermore, the product is notcaustic where fore it can be manipulated very easily.

When used as a fertilizer the product offers great advantages on accountof the fact that it contains ready-formed nitratenitrogen, and hereby ithas the advantages of lime nitrogen and Chile saltpeter without beingaffected with the inconveniences of the same.

Having now described our invention, what we claim as new and desire toters Patent is:

1. The herein described method of treating lime nitrogen which consistsin adding to the same 15-5O per cent. by weight of diluted nitric acidcontaining 3-25 per cent. of HNO substantially asdescribed and for thepurpose set forth.

2. The herein described method of treating lime nitrogen which consistsin adding to the same 1550 per cent. by weight of a diluted nitric acidcontaining 325 per cent. of HNO and cooling the mass during thetreatment, substantially as described and for the purpose set forth.

signed our names in the presence of two sub scribing witnesses.

ADOLF PAULINUS ZAMORE. OSCAR FREDRIK CARLSON.

Witnesses to the signature of A. P. Zamore:

CARL AxnL FREDRIK EHRNER, KANN AF. TROLLE. Witnesses to the signature ofO. F. Carl son;

Axnr. Sonnnruun, HILDING JoHANSsQN.

fiopies of this patent may be obtained for five cents each, byaddressing the Commissioner of 'iatent Washington, C.

secure by Let- In witness whereof, we have hereunto

